Composer and trumpeter Wadada Leo Smith has spent decades in musical experimentation, winning awards, devising a musical language and working with a remarkable list of artists. In that time, he’s made a few discoveries. “The greatest thing that connects people together,” said Smith, “is the ability to communicate.” When he and his Golden Quintet participate in the Impulse Festival of Improvisation at the University of Virginia, an event that climaxes with the ensemble’s multimedia performance of “America’s National Parks,” they’ll have plenty to say and demonstrate.